Defining custom fields

Note about numbers: Although you could store numbers as text strings, storing them in number fields will make a difference when you try to sort posts based on the numbers stored here (numbers will sort as 1,2,3,9,10,11 whereas text strings would sort as 1,10,11,2,3,9)

You can define as many custom fields of each type as you want and give them a name each. Each custom field has a field index which can be generated from the field name. The field index is the trimmed lowercase value of the field name where the white spaces are converted to one single underline character. Field indexes must be unique in a blog ( this way field names are also unique ).